Mounting of engine gears



Dec. 9, 1924- 1,518,360

F H. ROYCE MOYUNTING OF ENGINE GEARS Filed May14, 1924 FnEoER//r HENRY Abra:

y tromel 1 Patented Dec. 9, 1924.

UNITED sATEs PATENT OFFICE,

FREDERICK HENEA? ROYCE, en DERBY, ENGLAND, AssIGNoE To ROLLS ROYCE LIMITED, or DERBY, ENGLAND.

MOUNTING 0F ENGINE GEARS.

Application ledl May 14, 1924. Serial No. 713,286.

To all whom t may concern:

Be it ,known that I, FREDERICK HENRY ROYCE, residing at Derb England, a subject of the King of Great Britain and Ireland, have invented certainfnew and useful llmprovements in the Mounting of Engine Gears, of which the following is a specification.

This invention has reference to the mounting of the gears of engines and is useful in particular in connection with the half time gear of internal combustion engines. 'lhe object of the invention is to produce a friction-damped resilient drive between the engine -shaft and a pinion mounted thereon in which there shall be no rotational slack in the damping device and no end slack as between the pinion and the engine shaft, either of which if present might occasion objectionable noise. n

ln some. or all of the damped resilient' drives heretofore used for the half-time gear of internal combustion engines, the damping has been effected through the agency of brake shoes anchored to the pinion by pinned joints or by means of friction discs coupling the pinion and the shaft by means of serrations or teeth. lin all such cases there is a rotational slack, inthe former case in the pinned joints, and in the latter in the serrations or teeth, which under certain conditions producethe objectionable noise referred to.

According to my inventionl the gear 'is made as follows The spring drive may be' of any suitableJ form but is preferabl as hereinafter described.v The resilient rive is damped, and all end slack eliminated (the importance of which is greater in the ease of helical gearing) by a friction device in which a plate on disc rigidly mounted on the pinion or the hub thereof is pressed against a plate or disc ri idly mounted on the shaft by a spring loa ed pressure plate mounted on or carried by the shaft and rotationally rigid therewith, the plate or disc and the pressure plate being furnished with suitable friction surfaces, and the tension of the springs being such as to prevent any axial relative movement of the said plates or discs while allowing the desired rotational relative movement to permit the resilient drive to be effective..

An embodiment of my invention is illustrated in the accompanyin drawings in which Fig. 1 is a sectional e evation of the spring drive online Y-Y of Fig. 2, which latter "figure is an end sectional view on an enlarged scale on line X-X of Fig. l. I the construction shown in the drawings ther is mounted on and rigidl attached to the driving shaft a of the englne .a drum b having two diameters b1 and b2, the rim of each part beingcylindrical and concentric with the shaft a and the base both of the smaller part and the larger part being at right angles to the shaft. 'lhe outer rim of the larger part is utilised for the purpose of carrying a slipper ily-wheel lt.

The crank shaft a has a tapered part a1, a threaded part a2, and a keyway formed therein as at a3. The drum b has an interiorly tapered portion b3 fitting the tapered part a1 of the shaft, and the outer end of this portion b3 has applied to it a nut or collar b4; said drum being secured against axial movement by a nut a1 screwed on the threaded shaft part a2. The nut a4l has an. external flange at which overlaps an internal ange 54 on the nut or collar bt so that when the nut at is unscrewed the said flanges will engage and the drum be drawn off the shaft.

The pinion c of the gearis mounted on the shaft a outside the open end of the drum Zn, and has a hub c1 with interposed sleeve c2 extended along the shaft into the interior of the smallerv diameter part of the drum.

A ring f of metal, constituting a pressure plate for the friction device about` to be described, slidably iits in the small part of the drum Z) and has bored in one face alternately .a number of holes f1 forming pockets for helical springs f3 and a number of other holes f2 to receive with a close fit pins f4 carried on the base of the smaller part of the drum. .The said ins f4 do not extend to the full depth of t e holes f2 so that the presser plate, so far as such pins are concerned, can move axially while the pins prevent it from moving rotationally in relation to the base of the drum b, and hence in relation to the shaft a.

Two annular members d and d1 are connected by bolts d2 and nuts d3 to the base of the larger part of the drum b, the inner member d being a flat late or disc which extends inwards towar s the shaft (wlth, however, a clearance between it and the shaft) and acts as the outer plate of thev friction-device. Theouter annular member d1 is of l.shape in section-so thatwith one of its arms bolted as aforesaid, the other arm forms an annular fiat ring concentric with, but at a considerable distance from, the hub c1 of the pinion 0. Extending inwardly from said ring are a number of V-shaped projections d4, the apex of each of which is directed inwards towards the shaft, and each sideof which forms a fiat 'surface suitable for a helical spring e to iminge on. There are attached t0 or formed integrally with the hub c1 of pinion c, either extended from the face thereof lor otherwise, projections c4 also approximatel V-shaped with the apices turned inwardls and each side being suitably shaped to re- I ceive and hold the opposite ends ofthe spiral springs c by means of a suitable locating lug c5. rllhe said projections d4 and c4 on the ring and pinion respectively interlock and there is installed between each of the projections d4 and the adjacent projection o-one of the spiral springs e.-

An annular plate or dise g provided with a sleeve hub g1 Which-extends on either side thereof and which is internally tapered to fit and correspond with a tapered part of the hub 01 of the pinion 0, is rigidly mounted onjthe sleeve hub of the pinion by means of a key g2. The disc g is held against axial movement on the sleeve by nut g3.

The said annular plate g is located be-A tween -the pressure plate f above referred to and the annularlmember d previously described as forming the end plate of the friction device, there being interposed between thetparts mentioned friction washers g4. The disc g is pressed by said pressure VYfriction device constituted by the disc g and washers g4 compressed between the plate d and the spring loaded annular member f whereby oscillation is damped out and,

owing to the springs f3, all end slack is eliminated.

What I claim as my invention and desire to secure by Letters Patent of the United States 1. In gearing for internal combustion engines, the combination, with an engine shaft, of a gear rotatively mounted thereon; alternate, spaced projections associated with the shaft and gear extending outwardly from the latter and inwardly from the former; springs interposed between the projections of the shaft and gear, respectively; and frictionally-engaging members consisting of a plate rigidly secured to the gear, a plate rigidly secured to the shaft, and a springloaded pressure member adapted to press said plates together with frictional contact.

2. 'n gearing for internal combustion engines, the combination, with an engine shaft, of a gear having a sleeve mounted on the shaft for rotation thereon, lugs projecting radially outwards from said sleeve, a drum rigidly mounted on the shaft, lugs projecting radially inwards from the drum and spaced relatively to said lugs on the sleeve, helical springs interposed between the lugs of the sleeve and drum, frictionally engaging members rigidly mounted on said shaft and gear, and spring means for ensuring engagement of said friction members.

3. In gearing for internal combustion engines, the combination, with an engine shaft, of a gear rotatively mounted thereon, alternate spaced projections associated with the shaft and gear extending outwardly from the latter and inwardly from the former, springs interposed between the projections of the shaft and gear respectively, frictionally engaging members carried by said shaft and gear, an annular element associated with said friction members and provided with spaced apertures, and springs and pins associated with the shaft adapted to engage alternate ones of said apertures.

4. In gearing for internal combustion engines, the combination, with an engine shaft, of a gear having a sleeve mounted on the shaft for rotation thereon, lugs projecting radially outwards from said sleeve, a drum rigidly mounted on the shaft, lugs projecting radially inwards from the drum and spaced relatively to said lugs on the sleeve, helical springs interposed between the lugs of the sleeve and drum', frictionally engagmg members rigidly mounted on said shaft and gear, sprin means for ensuring engagement ot' said riction members, a nut applied to the end of the shaft, a nut applied to the adjacent end of the drum, and overlapping flanges on said nuts adapted for engagement when the first-mentioned nut is removed from the shaft.

In witness whereof I have signed this specification.

FREDERICK-HENRY ROYCE.

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